1. Field of the Invention
This invention relates to water supply valves, and more particularly to tank ballcock valves that are used to re-supply water to reservoir tanks for domestic commodes.
2. Background
Ballcock valves for refilling water reservoir tanks for domestic commodes have been in use for many years and are well known to the people who install them or replace them. Typically, these valves utilize a plug that is forced down to shut the water inlet by a pivoted arm that is levered by a tank float. The plug and internal valve structure usually include various flexible washers that perform vital functions in controlling valve internal water flow.
Over the past decade that has seen the introduction of fluorides, chlorine and other chemicals into the public water supply, there has been a reported notable increase in valve blockages interfering with proper operation of these valves. Often, the blockage is due to swelling of valve washers caused by chloramines in the water over a time period, the swollen washers then blocking discharge apertures. The only available solution to date has been to replace the plug and thereby the washers. This is usually only a temporary Solution as the blockage will probably re-occur in time.
Valve blockages are also caused by particles that may be floating in the water and blocking small diameter valve apertures, often occurring after work is done nearby on the water mains and the water supply may be temporarily muddy. The valve must then be opened in order to clean out these particles, which may be a time consuming job.
Another occasional problem in ballcock valve operation may arise when water "hammer" occurs in the water supply line. If this should happen during refill when the valve plug or stem is up and the flow chamber is open to inlet water pressure, the valve plug may be forced upwards too high or even out of the valve chamber, resulting in flooding the tank as well as the bathroom area around the toilet. Thus, there remain several ongoing valve operating problems that afflict the typical plug type ballcock valve in use today, resulting in much unavoidable repair and replacement costs. The present invention incorporates a valve design that solves these problems while keeping the familiar attributes of the ballcock valve for acceptance in domestic use.